Home made Natto – Welcome to Natto King!

If you are a Natto lover and like to make your own @ home, please read on and you’ll know how to make Natto.

This is a typical way of serving Natto and usually served as part of breakfast.

Well, if you don’t know about Natto and how it is very good for you, it may be worth it to check it out!

We are recently featured in OPB’s Arts & Life page.

if you, your friends and your family is living in Portland, please spread the words as we offer Home made Natto makings as part of HeidiNestler.com.

Making Natto at home in a nut shell.

It is not that difficult to successfully home brew Natto once you understand the absolute minimum requirements.

Temperature – This is the most critical factor in making Natto and any fermenter will probably agree. During the fermentation cycle, the temperature of Natto should be kept in the range between 38 – 45 C (100-113 degrees F). While many “How To” documents says around 40 (104 F), it is OK to keep it higher. Important is not to get below 38 degrees. However, if you keep it too high (more than 45 C), your Natto will be less sticky.

Time - Fermentation process should take approximately 24 hours. However, this is definitely experimental. I have tried to brew it for up to 48 hours and it all worked with slightly different results.

Aging – While you can eat the beans any time, for the better experience, age Natto for at least 24 hours in the fridge.

Soybeans – Use organic and Non GMO soybeans. Actually, this should be the number one rule and I think you know why.

Natto-kin (Starter) – Make sure that you have very active Natto-kin available.

OK, now. Let’s go over the basic steps to make stinky-sticky-delicious Natto.

Rinse Soybeans with running water.

Soak the beans with good water until it gets 3x the original size.

Steam or boil until the beans are soft. (You should be able to smash it by pinching.)

Mix the beans with Natto-kin.

Keep the beans fermenting for 24 hours keeping the temperature at around 40.

Age Natto in refrigerator for at least 24 hours.

See, it’s a no brainier, right?

Step by Step (How to make Natto.)

Here are the list of things that you need to get started with Home Brewed Natto. (HBN)

Organic Soybeans (I’ve been using organic soybeans that I purchased from our coop and I am very pleased with how they come out.)

Water (I ‘ve been using filtered water to soak beans and steam the beans.)

Starter {Natto-kin] There are several options for this and I will discuss this later.

Glass bowl(s) or container for soaking and fermenting and aging.

Kitchen themometer (I used remote one for this actual process and I love it.)

Pressure cooker. ( I highly recommend steaming the beans rather than boiling and with pressure cooker, my life is much easier.)

Cooler

Step. 1 – Washing beans

I scooped up 5 cups of dry soybeans and washed them quickly using running water . The process is much like washing rice properly.

Pour the beans into a glass bowl that is deep enough to mess around with the beans without spilling them.

Pour full of water so that all beans are submerged.

Stir beans for 20 sec. and flush the water out of the bowl.

Pour water back in the bowl to cover up just the surface of beans.

Stir beans but more like you are kneading the beans with your palm or the back of your hand. This process gets rid of tiny dirt or dead skins off the beans.

Rinse the beans with a lot of water.

Step. 2 – Soaking beans

After rinsing the beans, I pour plenty of flittered water into the bowl . The water should be at least three times the actual beans. So, I must have poured 15 cups of water or more . I let it sit overnight so that I can steam them first thing in the morning. There is a good reason for steaming the beans early morning and you’ll find that out later .

Step. 3 – Steaming beansOK, time for some more . I use a pressure cooker to steam the beans. I have tried boiling the beans in the past as we did not have a pressure cooker. First of all, it takes ages (4-5 hours)to boil the beans until they get soft enough for fermentation process. Secondly, it is a pain and kind of dangerous to drain boiling water and place the beans in the container for mixing them with the starters. Finally and most importantly, in my humble opinion, Natto is more rich in flavor when steamed than boiled.

I place the separator at the bottom. It’s about one inch high and it is high enough to separate boiling water from the steamer. You can use as little as a cup of water to do the steaming.

I love this insert. It is so easy to handle even right after steaming is done and beans are literally steaming hot.I pour soaked beans into this insert after rising it for one last time. I filled the pressure cooker with flittered water just below the bottom of the insert. I don’t think you can go wrong even if the some parts of beans are actually under the water but I would not dare.

I then sealed the pot with the lid and turn on the gas stove at high. I waited until the pressure indicator or what ever that is to pop and then lower the heat . I set kitchen timer for 45 minutes and leave the stove on.

I even lowered the heat when the steam would start come out the pressure cooker.

Step 4 – Mixing Natto-kin (Starter) with steaming hot beans

Natto-kin can live in extreme circumstance and mixing the starter with steaming hot beans would not kill the bacteria. In fact, it is recommended to mix beans with the starter while the beans are hot. Apparently, the “Heat Shock” should boost the bacteria activity and ensure better fermentation results.

Natto-kin (Starter) can be obtained in various ways.

From commercial product. (Natto themselves can be starters.)

Powdered Natto starter.

From home brew Natto.

I have been using Natto that we buy from our near by stores.

Typical Natto comes in the rectangular or round packages. You also find mustard and flavored soy sauce in a plastic containers.

I used a entire package (50g) for 5 cups of soybeans.

1 cup = 10g

Very straight forward.

I added boiling hot water to the starter package . Stir it a couple of times making sure that all beans are a part.

Pour the starter mix over the steamed beans that are place in the glass container. For the best result, use same container to mix and ferment to save you from washing yet another sticky bowl.

I would use wooden spatula to mix the beans with the starters. Mixing should be done quickly and thoroughly while making sure you don’t smash too many beans. Since the steamed beans start drying as soon as you pour them into the container, it is important that all beans are loose and wet by the starter mix.

Step 5 – Fermentation

In order to ferment soybeans, you need to have place that is dark, wet and warm. I personally hate such environment but Natto-kin love it. I own a piece of equipment that is actually called a Natto Maker but it is not readily available in the US. I brought it back from Japan and it wasn’t cheap. Also, it can only ferment up to 2 cups at time. Although it is probably a good size for a family, I had to seek an alternative way to ferment a large amount of beans and also some thing that is easy to get locally.

After extensive research (not!), I decided to use a cooler box and a kitchen thermometer.

The above photos are taken after 24 hours after the first batch was in the box for fermentation. When you place the container that is covered with aluminum foil with punctures for air, the temperature goes up to 75 C, and that was OK. Every hour, the temperature went down by 5C and it was around 45 when it was time to go to bed. I placed a plastic bottle filled with hot water around 80. The cooler (warmer) kept the temperature above 40c until noon next day. In that morning I prepared another 5 cups of hot water and placed them in the box . The remote kitchen thermometer was great for monitoring the temperature while working on other projects.

Step 6 – Aging

When the fermentation process is complete, Natto is covered with thin film of Natto-kin. Be aware of the overwhelming smell that once my dear friend described as “smelly feet”. But, for Natto lover , it is a smell of yumminess.

This time, despite the first experiment using “cooler” and large amount of soybeans, the result was quite satisfactory. The success matrix here is the stickiness of Natto. Smelly but not sticky Natto is like fancy web site with a very little traffic.

I’ve seen both, but , you can still eat beans even if fails to produce a beautiful web of yummyness.

Successfully, fermented Natto should taste good at this point. I highly encourage you to taste Natto at this stage so that you can really appreciate the aging process.

Natto can be in the aging process for forever. It should not go bad but it may dry up.

In a practical situation, it should be aged as short as 3 hours and as long as up to one week or however long your supply may last.I am aging both the first and second batch as I crank up this web page for the event. They are aging for 2 days now, and by the time I serve them 3 days.

I have to confess, our family has been nibbling off the batch I am preparing for the fermnetation festival and we are all happy about how they are doing.